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A TextView to prevent a bug with spans on JellyBean: http://code.google.com/p/android/issues/detail?id=35466
// Copyright 2012 Pierre-Yves Ricau
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
package info.piwai.android;
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.text.SpannableStringBuilder;
import android.text.Spanned;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.TextView;
/**
* <p>
* A {@link TextView} that insert spaces around its text spans where needed to
* prevent {@link IndexOutOfBoundsException} in {@link #onMeasure(int, int)} on
* Jelly Bean.
* <p>
* When {@link #onMeasure(int, int)} throws an exception, we try to fix the text
* by adding spaces around spans, until it works again. We then try removing
* some of the added spans, to minimize the insertions.
* <p>
* The fix is time consuming (a few ms, it depends on the size of your text),
* but it should only happen once per text change.
* <p>
* See http://code.google.com/p/android/issues/detail?id=35466
*
* @author "Pierre-Yves Ricau" <py.ricau@gmail.com>
*
*/
public class JellyBeanSpanFixTextView extends TextView {
private static class FixingResult {
public final boolean fixed;
public final List<Object> spansWithSpacesBefore;
public final List<Object> spansWithSpacesAfter;
public static FixingResult fixed(List<Object> spansWithSpacesBefore, List<Object> spansWithSpacesAfter) {
return new FixingResult(true, spansWithSpacesBefore, spansWithSpacesAfter);
}
public static FixingResult notFixed() {
return new FixingResult(false, null, null);
}
private FixingResult(boolean fixed, List<Object> spansWithSpacesBefore, List<Object> spansWithSpacesAfter) {
this.fixed = fixed;
this.spansWithSpacesBefore = spansWithSpacesBefore;
this.spansWithSpacesAfter = spansWithSpacesAfter;
}
}
private static final String TAG = JellyBeanSpanFixTextView.class.getSimpleName();
public JellyBeanSpanFixTextView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public JellyBeanSpanFixTextView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public JellyBeanSpanFixTextView(Context context) {
super(context);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
try {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
} catch (IndexOutOfBoundsException e) {
fixOnMeasure(widthMeasureSpec, heightMeasureSpec);
}
}
/**
* If possible, fixes the Spanned text by adding spaces around spans when
* needed.
*/
private void fixOnMeasure(int widthMeasureSpec, int heightMeasureSpec) {
CharSequence text = getText();
if (text instanceof Spanned) {
SpannableStringBuilder builder = new SpannableStringBuilder(text);
fixSpannedWithSpaces(builder, widthMeasureSpec, heightMeasureSpec);
} else {
if (BuildConfig.DEBUG) {
Log.d(TAG, "The text isn't a Spanned");
}
fallbackToString(widthMeasureSpec, heightMeasureSpec);
}
}
/**
* Add spaces around spans until the text is fixed, and then removes the
* unneeded spaces
*/
private void fixSpannedWithSpaces(SpannableStringBuilder builder, int widthMeasureSpec, int heightMeasureSpec) {
long startFix = System.currentTimeMillis();
FixingResult result = addSpacesAroundSpansUntilFixed(builder, widthMeasureSpec, heightMeasureSpec);
if (result.fixed) {
removeUnneededSpaces(widthMeasureSpec, heightMeasureSpec, builder, result);
} else {
fallbackToString(widthMeasureSpec, heightMeasureSpec);
}
if (BuildConfig.DEBUG) {
long fixDuration = System.currentTimeMillis() - startFix;
Log.d(TAG, "fixSpannedWithSpaces() duration in ms: " + fixDuration);
}
}
private FixingResult addSpacesAroundSpansUntilFixed(SpannableStringBuilder builder, int widthMeasureSpec, int heightMeasureSpec) {
Object[] spans = builder.getSpans(0, builder.length(), Object.class);
List<Object> spansWithSpacesBefore = new ArrayList<Object>(spans.length);
List<Object> spansWithSpacesAfter = new ArrayList<Object>(spans.length);
for (Object span : spans) {
int spanStart = builder.getSpanStart(span);
if (isNotSpace(builder, spanStart - 1)) {
builder.insert(spanStart, " ");
spansWithSpacesBefore.add(span);
}
int spanEnd = builder.getSpanEnd(span);
if (isNotSpace(builder, spanEnd)) {
builder.insert(spanEnd, " ");
spansWithSpacesAfter.add(span);
}
try {
setTextAndMeasure(builder, widthMeasureSpec, heightMeasureSpec);
return FixingResult.fixed(spansWithSpacesBefore, spansWithSpacesAfter);
} catch (IndexOutOfBoundsException notFixed) {
}
}
if (BuildConfig.DEBUG) {
Log.d(TAG, "Could not fix the Spanned by adding spaces around spans");
}
return FixingResult.notFixed();
}
private boolean isNotSpace(CharSequence text, int where) {
return text.charAt(where) != ' ';
}
private void setTextAndMeasure(CharSequence text, int widthMeasureSpec, int heightMeasureSpec) {
setText(text);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
private void removeUnneededSpaces(int widthMeasureSpec, int heightMeasureSpec, SpannableStringBuilder builder, FixingResult result) {
for (Object span : result.spansWithSpacesAfter) {
int spanEnd = builder.getSpanEnd(span);
builder.delete(spanEnd, spanEnd + 1);
try {
setTextAndMeasure(builder, widthMeasureSpec, heightMeasureSpec);
} catch (IndexOutOfBoundsException ignored) {
builder.insert(spanEnd, " ");
}
}
boolean needReset = true;
for (Object span : result.spansWithSpacesBefore) {
int spanStart = builder.getSpanStart(span);
builder.delete(spanStart - 1, spanStart);
try {
setTextAndMeasure(builder, widthMeasureSpec, heightMeasureSpec);
needReset = false;
} catch (IndexOutOfBoundsException ignored) {
needReset = true;
int newSpanStart = spanStart - 1;
builder.insert(newSpanStart, " ");
}
}
if (needReset) {
setText(builder);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
}
private void fallbackToString(int widthMeasureSpec, int heightMeasureSpec) {
if (BuildConfig.DEBUG) {
Log.d(TAG, "Fallback to unspanned text");
}
String fallbackText = getText().toString();
setTextAndMeasure(fallbackText, widthMeasureSpec, heightMeasureSpec);
}
}
@optimike

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commented Sep 20, 2012

calling from line 122 with (spanStart - 1), isNotSpace can also return IndexOutOfBounds exception is spanStart = 0. I've changed isNotSpace to return true if 'where < 0'.

@djmedic913

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commented Oct 17, 2012

I apologize for this but I am still a relative newbie. How do I add this to my app to fix this Nexus issue?

@extralam

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commented Aug 15, 2014

private boolean isNotSpace(CharSequence text, int where) {
if (where < 0 || where >= text.length()) {
return true;
}
return text.charAt(where) != ' ';
}

@girish3

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commented Jan 14, 2015

super.onMeasure() is causing the error in generating signed apk but the code is
working on the emulator. I tried replacing it with super.measure but then code breaks.
Can anybody help me on this ?

@ultraon

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commented Oct 19, 2015

Need to fix and simplify isNotSpace() method:

    private boolean isNotSpace(CharSequence text, int where) {
        return where < 0 || where >= text.length() || text.charAt(where) != ' ';
    }

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